Some of the most frequently used buzzwords in contemporary urban environments and planning discourses include terms such as ‘green cities’, resilience, sustainability and densification. These terms are used in diverse contexts and with multiple meanings making the distinction of meanings difficult to trace. In the context, though, of architecture and urban planning the term ‘sustainability’ combined with the term ‘densification’ often seems to presuppose that densification will automatically lead to sustainability. At the same time, the so called ‘green cultural heritage’ is rarely put forward in urban planning processes. This then raises the question: how does the aspiration for resilient and sustainable green cities meet the need for caring for green cultural heritage such as urban public parks, private gardens, residential areas etc.? Moreover, how does intense planning for more densely populated cities meet the growing needs of urban citizens for green, clean and recreational areas – without damaging green cultural heritage places? It is the aim of this chapter to explore these difficult and complex questions. The chapter is informed by my experience in Stockholm, Sweden, in order to unfold the tension between the ways in which green cultural heritage can drive urban sustainable development, on the one hand, and the ways in which green cultural heritage spaces can be sustained and preserved. The chapter further argues that integrating green cultural heritage into a deep cities approach, which looks at the historical layers of a city, is of vital significance as green spaces have a historic, multi-layered past that needs to be integrated into a constantly evolving urban environment. Establishing novel ways in which this integration can be achieved is one of the next challenges for sustainable ‘deep’ cities.